A display panel includes an array substrate and an alignment substrate arranged to be opposite to the array substrate, wherein both of the array substrate and the alignment substrate are manufactured by a series of production processes.
A glass substrate used for manufacturing the array substrate or the alignment substrate is transported among various process equipments in a process of manufacturing the array substrate or the alignment substrate, and the glass substrate frequently contacts and collides with transfer equipment in a transportation process, so that the glass substrate is likely to be damaged, resulting in that the manufactured array substrate or alignment substrate cannot be used. More seriously, when the damaged glass substrate is processed, residual glass fragments on the glass substrate result in blockage and scratch damage to the process equipment to cause serious economic loss.
Therefore, how to effectively detect whether the glass substrate is damaged in time is particularly important in the display panel manufacturing industry.